Acceleration sensors, gyro-sensors, and the like are provided with semiconductor devices including a movable portion displaced by force externally applied (hereinafter, referred to as external force), such as MEMS (micro-electro-mechanical system) devices. For example, capacitive acceleration sensors which sense a change in capacitance between two beam-type oscillators to detect acceleration have been put to practical use.
In recent years, MEMS devices including an isolation region between the free end of the beam-type movable portion and a substrate supporting the movable portion have been proposed (for example, see Patent Literature 1). Specifically, a groove for isolation is formed between the free end of the movable portion and the fixed end of the movable portion fixed to the substrate. The groove is filled with an insulating material to form the isolation region electrically separating the free end of the movable portion and the substrate.
Citation List
Patent Literature 1: U.S. Pat. No. 6,342,430